Chuck or work-holder.



No. 687,533. Patented Nov. 26, |901.

' T. KITCHIN.

CHUCK DRWORK HOLDER.

(Application led May 21, 19401.) (No Model.)

I E l5 A l la 1),; 5,120@ 129.1,

Witness-es. V

Inventor.

we Nonaxs PETERS no. Puoroujno. wAsHmGYmg. D. n

UNITED STATES PATENT EEICE.

THOMAS KITCHIN, OF PHILADELPHIA, PENNSYLVANIA.

CHUCK OF!v WORK-HOLDER.

SPECIFICATION forming part of Letters Patent No. 687,533, dated November26, 14901.

Application tiled May 21,1901.

To @ZZ whom t may concern.-

Be it known that I, THOMAS KITCHIN, a citizen of the United States,residing in the city and county of Philadelphia, in the State ofPennsylvania, have invented certain new and usefullmprovementsin Chucksor Work- Holders, of which the following is a full, clear, and exactdescription, reference being had to the accompanying drawings, forming apart of this specification.

This invention is a chuck or work-holder of simple and efficientconstruction and operation designed for use more especially inconnection with or. as an attachment for grinding-machines to facilitateand insure the accurate grinding internally of bushings and othertubular devices of varying lengths and diameters.

The invention, stated generally, compLises in a chuck a bodily-rotatablesleeve or hollow support having thereon a pair of oppositely disposedlongitudinally adjustable members carrying each a set ofradially-movable jaws, which extend through longitudinal openings in thewall ot the sleeve, and coacting connections between said members andtheir respective jaws, whereby said members and their jaws may be bodilyadjusted longitudinally of the sleeve and whereby the jaws may beadjusted radially of the sleeve. The said chuck is adapted to be mountedeccentrically in respect to the grinding-wheel and its shaft to the endthat the inner'wall of the bushing will be presented progressively tosaid wheel.

The invention also comprises various novel constructions andcombinations of parts, which will be hereinafter particularly describedand claimed.

In the drawings, Figure 1 is a plan of a chuck embodying my invention.Fig. 2 is a vertical section thereof as on the line 2 2 of Fig. 1,showing a portion of a bushing held thereby. Fig. 3 is a transversesection as on the line 3 8 of Fig. 2. Fig. 4. is a partial transversesection, enlarged, as on the line 4 4 of Fig. 1. Fig. 5 is a verticalsection as on the line 5 5 of Fig. 4.

A is a bracket or support of suitable shape and size for its intendedpurpose. present instance it comprises a base a, with overhanginguprights a', in which are pro- Serial No. 61,233. (No model.)

vided boxes or bearings a2 for a rotatable sleeve B. This sleeveisequipped at one end with a pulley b, by means of which it may bepositively driven. It is also externally screw-threaded from `about themiddle of its periphery toward its respective ends, one portion beingprovided with a right-hand thread b and the other with a left-handthread b2. Each portion Vis also provided with a series ofequally-spaced longitudinal slots b-iu the present instance three.Screwed on to the respective ends of the sleeve are rings D D',respectively, provided each with three radially-movable jaws d, that eX-tend through the adjacent slots in the sleeve. One side ot each of thejaws is provided throughout its length with a series of teeth d',similarly to a gear-rack,and the inner extremity of the jaw ispreferably shouldered, as'at cl2. Rotatably fitted to a circumferentialgroove in each of the rings is an independent ring d3, on one face ofwhich is a spiral thread d, which coact-s with the teeth of theproximate jaws, whereby when the ring d3 is properly turned the severaljaws connected therewith will be moved as a unit radially toward or fromthe center of the sleeve, as desired. This ring cl3 is preferablyprovided with radially-extending handles to facilitate its manipulation.

Each ofthe rings D D is preferably, though not essentially, formed intwo parts, one part no being of L shape cross section, provided in itsvertical flange with radial dovetail grooves for the reception andguidance of the radially-movable jaws, which in cross-section match thegrooves, and the other part y beinga plain backing-ring screwed orotherwise affixed to the horizontal flange of the part m to aord thecircumferential groove for the` work, thereby securely clamping andcentering the same within the sleeve. The shaft F- of thegrinding-machine extendseccentrically through the sleeve, so that theinner wall ot the bushing during the rotation of the chuck is presentedprogressively to the grindingwheelfon said shaft.

The threads of the companion rings D d3 are right hand and the threadsof the com? panion rings D' d3 left hand. IIence by reason of thenecessary direction of movement et the sleeve in its bearings, asindicated by the arrow in Fig. 3, a secure and effective clamping of thejaws upon the work is insured during the grinding operation.

It will be seen that owing to their capacity for adjustmentlongitudinally of the axis of the sleeve, as well as radially thereof,the jaws may be applied to work ot Varying lengths and diameters.

I claiml. In achuck,an externally-threaded sleeve provided withlongitudinal slots or openings,

a threaded ring screwed onto said sleeve, ra dially-movable jaws in saidring provided able toward andfrom each other, radiallymovable jaws insaid membersV provided with gear-teeth, and rings on -said membersprovided with spiral threads coacting with the teeth of the respectivejaws.

4. The combination with a supporting member provided with boxes orbearings,of asleeve mounted therein provided with oppositelydisposedscrew-threads on its periphery and with longitudinal slots,screw-threaded rings fitted to the respective threaded portions of thesleeve, jaws in said -rings movable radially through the slots in thesleeve, said jaws being provided with gear-teeth, and rotatable memberson said rings provided with spiral threads coacting with the teeth ofthe jaws, respectively.

5. The combination witha supporting memberprovided with boxes orbearingstasleeve mounted therein provided with Yoppositelydisposedscrew-threads on its periphery and withlongitudinal slots,screw-threaded rings fitted to the respective threaded portions ot thesleeve, jaws in said rings movable radially through the slots in thesleeve, said jaws being provided with gear-teeth, and being shoulderedat their inner extremities, and rotatable members on said rings providedwith vspiral threads coacting with the teeth of the jaws THOMAS KITCHIN.

Witnesses:

ANDREW V. GROUPE, JOHN R. NoLAN.

